A Level Chemistry Transition Unit

Beverley Joint 6th

A LEVEL CHEMISTRY TRANSITION UNIT

Name: ______

Secondary School ______

Contents
Introduction
Course Outline
Task 1: / The structure of atoms
Task 2: / Atoms and ions
Task 3: / Writing formulas
Task 4: / Relative masses
Task 5: / Balancing equations
Task 6: / Writing symbol equations from words
Task 7: / Using moles
Task 8: / Empirical and molecular formulae
Task 9: / Different types of structures
Task 10: / Alkanes and formulae
Task 11 / Products from fuels

Introduction

Some students find the transition from GCSE to A-level Chemistry very challenging. To help make this transition smoother and to give you the best possible start, we have prepared this booklet for you.

It is important that you read through this booklet and then complete all the questions. If you require more space then you can use lined paper.These must be organised in a folder.The tasks cover GCSE topics which you should have already covered. You will need a secure knowledge of these topics before you start the course in September. Task 11 must be completed by all students regardless of whether you have studied Triple Science.

At the beginning of the course you will be given a test to check how well you have understood the topics. If you do not pass this test, you will be put into an intervention class. This class will help you to bring your knowledge and understanding up to the required standard.

To help you complete this booklet the following resources may be useful:

• http://www.bbc.co.uk/schools/gcsebitesize/

• http://www.s-cool.co.uk/gcse

• Any GCSE Additional Science/ Chemistry revision guide

• Your own old GCSE Science/ Chemistry exercise books

• Head Start to AS Chemistry Published by CGP

The tasks in this booklet must be completed by the 1st day back at Beverley High School and will be presented to the teacher in your first Chemistry lesson.

Beverley Joint 6th Chemistry Teachers

Structure of lessons

There will be 4 timetabled lessons each week. You will be required to actively participate in lessons by asking and answering questions, contributing and sharing ideas.

Assessment

Assessment can take place:

1. During lessons

2. At the end of a topic

3. At the end of a unit

Any assessment will test for knowledge, understanding, application skills, analysis skills and evaluation skills.

Homework

You will be given homework on a regular basis, which must be completed in addition to reading around the subject and note making.

Resources

• Main textbook: Nelson Thornes AQA AS Chemistry

• Other texts: CGP AS Chemistry textbook

• AQA website

• Royal Society of Chemistry (sign up)

• Task 1:The structure of atoms

1 Complete the spaces to create a set of notes about the structure of atoms.

Atoms consist of a central ______containing protons and ______. The nucleus is ______compared to the size of the whole atom. The nucleus is surrounded by ______in energy levels (also called ______). Atoms have no electric charge because they contain the same number of protons and ______.

Sub-atomic / Relative mass Relative charge
particle

Proton

Neutron

Electron

Atomic number = number of ______.

Mass number = number of ______+ number of ______.

mass number / 19
Symbol / e.g. F
atomic number / 9
protons = / ______
neutrons = / ______
electrons = ______

Atoms of the same element have the same number of ______. It is the number of

______that determines what type of atom it is (e.g. all atoms with six protons are carbon atoms). Atoms of different elements have different numbers of ______. Isotopes are atoms of the same element. They contain the same number of ______but a different number of ______.

2 Complete the table about some atoms.

Atom / Atomic / Mass number / Number of / Number of / Number of
number / protons / neutrons / electrons
23 Na
11
Li / 3 / 7
Ar / 40 / 18
K / 19 / 20
Al / 14 / 13
Cl / 17 / 18

23592 U

23892U

Task 2:Atoms and ions

You will need to look at the Periodic Table to help you answer the following questions.

1 a Complete the table to show the electronic structure of the following ions.

Ion / F– / Na+ / Al3+ / K+ / S2– / H+ / O2– / Ca2+ / Li+ / Mg2+ / Cl– / Be2+
Electroni
c
structure

b Complete the table below to show the electronic structure of some Group 0 elements (noble gases).Place the ions from part ainto the correct row of the table.

Element / Electronic structure Ions with the same electronic structure

c i Complete the table with the ions from part a. Ions for Group 1 have been done for you. Do not include the H+ ion.

Group / 1 / 2 / 3 / 4 / 5 / 6 / 7 / 0
Ions / Li+ Na+
K+
Charge / +1

ii Predict the charge that the following ions would have using the Periodic Table and your table.

strontium ions ______iodide ions ______rubidium ions ______

2 Magnesium atoms react with fluorine atoms to form the ionic compound magnesium fluoride. Magnesium atoms each lose two electrons to form magnesium ions. Fluorine atoms each gain one electron to form fluoride ions. This means that magnesium atoms react with fluorine atoms in the ratio of one magnesium atom for every two fluorine atoms.

3 Complete the following table about some atoms and ions. The first row has been done for you.

Particle / Atom or / Atomic / Mass / Number of / Number of / Number of / Electronic
ion / number / number / protons / neutrons / electrons / structure
16O2– / ion / 8 / 16 / 8 / 8 / 10 / [2, 8]2–
31P
13 / 27 / 13
13 / 27 / 10
atom / 2 / 4
16 / 32 / [2, 8, 8]2–
12 / 12 / [2, 8]2+

Task 3:Writing formulas

Use the table of ions to write the formula of the following ionic compounds. Use the general rule of cross-multiply and then simplify where possible.

Eg: Aluminium oxide:

Al3+ O2-
X3 / X2
Al2 / 3
Positive ions / Negative ions
aluminium / Al3+ / lead / Pb2+ / bromide / Br– / oxide / O2–
ammonium / NH4+ / lithium / Li+ / carbonate / CO32– / sulfate / SO42–
barium / Ba2+ / magnesium / Mg2+ / chloride / Cl– / sulfide / S2–
magnesium / Ca2+ / potassium / K+ / fluoride / F–
copper (II) / Cu2+ / silver / Ag+ / hydrogencarbonate / HCO3–
hydrogen / H+ / sodium / Na+ / hydroxide / OH–
iron (II) / Fe2+ / zinc / Zn2+ / iodide / I–
iron (III) / Fe3+ / nitrate / NO3–
1 a / potassium iodide / 2 a / potassium sulfate
b / sodium oxide / b / magnesium sulfate
c / aluminium bromide / c / magnesium hydroxide
d / magnesium chloride / d / copper (II) nitrate
e / silver oxide / e / zinc carbonate
f / iron (II) oxide / f / potassium hydroxide
g / iron (III) oxide / g / sodium carbonate
h / magnesium sulfide / h / aluminium hydroxide
i / copper (II) chloride / i / ammonium hydroxide
j / lithium fluoride / j / ammonium chloride
k / barium chloride / k / aluminium sulfate

Task 4:Relative masses

Element / Ar / Element / Ar / Element / Ar
aluminium / Al / 27 / hydrogen / H / 1 / phosphorus / P / 31
bromine / Br / 80 / iodine / I / 127 / potassium / K / 39
magnesium / Ca / 40 / iron / Fe / 56 / silver / Ag / 108
carbon / C / 12 / magnesium / Mg / 24 / sodium / Na / 23
chlorine / Cl / 35.5 / nitrogen / N / 14 / sulfur / S / 32
copper / Cu / 63.5 / oxygen / O / 16 / zinc / Zn / 65
fluorine / F / 19

Calculate the relative formula mass of the following substances on page 9 . You will need to use the relative atomic masses (Ar) shown above.

(HINTS: 1.If there is formulae in brackets everything in the brackets need to be multiplied by the number outside.

2. The dot means to add. So for CuSO4.5H2O add CuSO4 to 5 lots of H2O).

aMg(OH)2 / e / (NH4)2SO4
bAl(NO3)3 / f / CuSO4.5H2O
cFe2(SO4)3 / g Na2CO3.10H2O
dCa(HCO3)2 / h Fe(NH4)2(SO4)2.6H2O

2 Calculate the percentage by mass of the element shown in each of the following substances. You will need to use the formula masses calculated in Q1.

a / O in Mg(OH)2 / e / N in (NH4)2SO4
b O in Al(NO3)3 / f / O in CuSO4.5H2O
c / O in Fe2(SO4)3 / g Na in Na2CO3.10H2O
d H in Ca(HCO3)2 / h Fe in Fe(NH4)2(SO4)2.6H2O

Task 5:Balancing equations

Balance the following equations.

a N2 + ______H2 → ______NH3 b ______Ca + O2 → ______CaO

c Br2 + ______KI → ______KBr + I2

d ______Fe + ______H2O → Fe3O4 + ______H2 e C3H8 + ______O2 → ______CO2 + ______H2O

f ______NH3 + ______O2 → ______NO + _____ H2O

Task 6:Writing symbol equations from words

Write symbol equations for the following reactions taking place. You will first need to convert the names of the materials into formulae and then balance the equation. Use the table to work out the

1. Zinc metal reacts with copper sulphate solution to produce solid copper metal and zinc sulphate solution.

2. Solid magnesium hydroxide reacts with solid ammonium chloride on heating to produce solid magnesium chloride, steam and ammonia gas.

3. When lead (II) nitrate is heated in a dry test tube lead (II) oxide, nitrogen dioxide gas and oxygen are produced.

4. Silicon tetrachloride reacts with water to produce solid silicon dioxide and hydrogen chloride gas.

5. When octane (C8H18) vapour is burned with excess air in a car engine carbon dioxide and water vapour are produced.

6. When rubidium reacts with water a solution of the hydroxide of the metal is produced as well as hydrogen gas.

7. When strontium reacts with water a solution of the hydroxide of the metal is produced as well as hydrogen gas.

8. Sodium chloride reacts with concentrated sulfuric acid to produce sodium hydrogen sulphate and hydrogen chloride.

Task 7:Using moles

1 Complete the blank parts of the following table.

Substance / Formula / Mr / Mass / Moles
carbon monoxide / CO / 560 g
propane / C3H8 / 0.2
unknown solid / unknown / 0.104 g / 0.0005
methane / CH4 / 6 kg
sodium carbonate / Na2CO3 / 2.5
unknown gas / unknown / 0.1 g / 0.0025

2 How many moles are there in each of the following?

a 72 g of Mg / moles = / mass / = / 72 / = 3 moles
Mr / 24

b 39 g of Al(OH)3 ______

c 1 tonne of NaCl ______

d 20 mg of Cu(NO3)2 ______

3 What is the mass of each of the following?

a 5 moles of Cl2 mass = Mr × moles = 71 × 5 = 355 g

b 0.2 moles of Al2O3 ______

c 0.002 moles of (NH4)2SO4______

d 0.3 moles of Na2CO3.10H2O ______

4 An experiment was carried out to find the Mr of vitamin C (ascorbic acid). It was found that 1 g contains 0.00568 moles of vitamin C molecules. Calculate the Mr of vitamin C.

Task 8:Empirical and molecular formulae

Empirical formula is the simplest whole number ratio of elements. Divide the percentage or mass by the Mr of each element in the compound, divide by the smallest number and simplify to give a whole number ratio.

Element / Ar / Element / Ar / Element / Ar
aluminium / Al / 27 / hydrogen / H / 1 / phosphorus / P / 31
bromine / Br / 80 / iodine / I / 127 / potassium / K / 39
magnesium / Ca / 40 / iron / Fe / 56 / silver / Ag / 108
carbon / C / 12 / lead / Pb / 207 / sodium / Na / 23
chlorine / Cl / 35.5 / magnesium / Mg / 24 / sulfur / S / 32
copper / Cu / 63.5 / nitrogen / N / 14 / zinc / Zn / 65
fluorine / F / 19 / oxygen / O / 16

1 Copy and complete the table.

Empirical formula / Mr / Molecular formula
CH2 / 42
C5H10
C4H8
C3H8 / 44
H2O2
CH / 78

2 Find the empirical formula of each of the following substances using the data about composition by mass.

a / H / 5% / F / 95%
b Na / 3.71 g / O / 1.29 g
c / Pb / 90.7% / O / 9.3%
d C / 60.0% / H / 13.3% / O 26.7%

3 3.53 g of iron reacts with chlorine to form 10.24 g of iron chloride. Find the empirical formula for the iron chloride.

4 Analysis of a compound consisting of carbon, hydrogen and oxygen showed it to contain 0.273 g C, 0.046 g H, and 0.182 g O. It has a relative formula mass (Mr) of 88.

a Calculate the empirical formula of the compound.

b Calculate the molecular formula of the compound.

Task 9: Different types of structures

Complete the table about substances with each of the types of structures shown.

Type of structure / Simple molecular / Ionic / Giant covalent / Metallic
Description of
the structure
Type of bonding
Melting and
boiling points
(with reason)
Electrical
conductivity
(with reason)
Exception:
Graphite
Which types of
substances have
this structure

Task 10:Alkanes and formulae